一对多双向--映射文件

public class Classes implements Serializable {

    private Long cid;
    private String name;
    private String description;
    private Set<Student> students;
    public Long getCid() {
        return cid;
    }
    public void setCid(Long cid) {
        this.cid = cid;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
    public Set<Student> getStudents() {
        return students;
    }
    public void setStudents(Set<Student> students) {
        this.students = students;
    }
}

public class Student implements Serializable{
    private Long sid;
    private String name;
    private String description;
    private Classes classes;
    public Long getSid() {
        return sid;
    }
    public void setSid(Long sid) {
        this.sid = sid;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
    public Classes getClasses() {
        return classes;
    }
    public void setClasses(Classes classes) {
        this.classes = classes;
    }

}

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.sn.domain.Classes">
        <id name="cid" type="java.lang.Long" length="5">
            <generator class="increment"></generator>
        </id>
        <property name="name" length="20"></property>
        <property name="description" length="50"></property>
        <set name="students" cascade="all" inverse="false">
            <key>
                <column name="cid"></column>
            </key>
            <one-to-many class="com.sn.domain.Student"/>
        </set>
    </class>
</hibernate-mapping>

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.sn.domain.Student">
        <id name="sid" type="java.lang.Long" length="5">
            <generator class="increment"></generator>
        </id>
        <property name="name" length="20"></property>
        <property name="description" length="50"></property>
        <many-to-one name="classes" column="cid" class="com.sn.domain.Classes"></many-to-one>
    </class>
</hibernate-mapping>